摘要
通过对原状膨胀土三轴剪切过程的CT扫描分析,结合CT数据及图像,发现其剪切受力破坏过程实际上是内部裂隙的扩张演化过程。在应力峰值之前,膨胀土的CT数一直在增加,同时CT数的方差减小,表明膨胀土的密度不断增加,在三向应力作用下,膨胀土变得相对均匀了;在峰值之后,情况正好相反,CT数一直在变小,CT数的方差变大,表明其密度不断减小,裂隙变得相对不均匀。裂隙是由中心向中部或边缘扩展,直至贯通和剪切面的形成。CT数的均值、方差随轴向变形变化关系曲线呈抛物线形式。
The CT scanning in triaxial shear test on original expansive soils is conducted.Combining images and data of the CT scanning with the stress-strain curve,it is found out that the shearing process of the samples is actually the development of interior fissure.Before deviatoric stress reaches the peak strength,the CT number increases and the variance of CT number decreases,which indicates that the density increases and the expansive soils become more homogenous.But,after the deviatoric stress exceeds the peak strength,things goes in opposite direction.The fissures develop from the center of the soil sample to the edge until they connect and form shearing faces.The relationship between mean of CT number and variance of CT number to axial deformation are parabolas.
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2004年第z1期4392-4395,共4页
Chinese Journal of Rock Mechanics and Engineering
基金
国家自然科学基金(59479017)
陕西省自然科学基金(97C22
2001C01)
地质灾害防治与工程地质环境保护国家专业实验室开放基金(99007)
西安公路交通大学青年科技发展项目资助课题。
关键词
土力学
损伤力学
膨胀土
结构性
强度
CT扫描
soil mechanics,damage mechanics,expansive soil,structural behavior,strength,CT scanning
